Structural changes in bulk MoS₂ as a consequence of 1.5 MeV proton micro beam irradiation

This article provides an overview of the structural changes in bulk MoS₂ flakes, post irradiation with 1.5 MeV proton micro beam. We have irradiated multilayer MoS₂ flakes, with 1.5 MeV proton micro beam in the fluence range 15-2135 pC/μm². The fluence has been varied at constant flux and energy in the quest of the optimized defect density. The impact of micro beam irradiation on the sample, has been assessed by Raman measurement. We have observed significant changes in the and A1g Raman vibrational modes of MoS₂ flakes post irradiation. The X-ray diffraction (XRD) studies demonstrate that there are systematic and significant structural changes in the MoS₂ flakes, due to 1.5 MeV proton micro beam irradiation. The XRD findings reveals that the formation of double phase takes place, with 706 pC/μm² of proton micro beam fluence at 1.5 MeV and beyond. Theoretical simulation to assess the defect density have been performed using stopping range of ions in matter software. (author)